Beccariophoenix alfredii Image
Beccariophoenix alfredii
Copyright © Mijoro Rakotoarinivo

Beccariophoenix alfredii

Family: Arecaceae    Palm Tree

Common Name: High Plateau Coconut Palm

Cold Hardiness Zone: 9a     View the UK and US zone maps

Identification:
A recently discovered Beccariophoenix originating in a valley west of Antsirabe on the high plateaux of Madagascar, 20° 12’ 32.1" S, 46° 30’ 04.3" E, at an elevation of 1050 m (3440 ft). It tolerates moderate frosts, and can be grown in a full sun or shaded positions. Beccariophoenix alfredii grows up to 50 ft (15 m) in height with a trunk up to 1 ft (30 cm) in diameter. The crown holds 30-36 pinnate leaves, which reach lengths of 4.5 m (15 ft). Each leaf holds approximately 120 pairs of leaflets. The leaflets are very slender and crowded at the base, and are either rigid or somewhat pendulous. The inflorescence is infrafoliar rather than interfoliar as in B. madagascariensis.

General Information:
Robust, solitary, unarmed, pleonanthic, monoecious, tree palm. Stem erect, to ca. 15 m tall, 28-30 cm diam. at breast height, grey-brown, eventually becoming bare and closely ringed with leaf scars, internodes ca. 2.5 cm. Leaves 30-36 in crown, pinnate, marcescent in juvenile palms, abscising neatly in adults; sheath tubular at first, to at least 82 cm long, with two lateral, ± entire, triangular lobes to 30 cm long, 10 cm wide at the base, tapering to ca. 8 cm, the abaxial surface of the sheath covered with thick caducous grey-brown indumentum, the body of the sheath disintegrating into a mass of robust sinuous grey fibres ca. 3 mm wide, adaxially the sheath glabrous, reddish-brown; petiole very short, ca. 4-5 cm long, to 8 x 2.3 cm wide and deep, with scattered caducous scales; rachis to at least 4.4 m long, to 7 x 2.3 cm wide and deep at the base, tapering gradually distally, adaxially ridged near the base, abaxially rounded, distally with 2 lateral grooves; leaflets ca. 120 on each side of the rachis, ± regularly arranged, very slender and crowded at the base, ± rigid or somewhat pendulous, ca. 47 x 1 cm at the base of the leaf, ca. 112 x 4 cm in mid leaf, ca. 65 x 1.8 cm at the tip, ± acute, easily splitting and becoming bifid, adaxially glabrous, abaxially lacking powdery white wax, transverse veinlets short, conspicuous, minute punctiform scales present on longitudinal veins. Inflorescences solitary, infrafoliar, branching to 1 order; peduncle moderate, 8-13 cm long, elliptic in cross-section, 4 x 1.7 cm, with caducous grey-brown indumentum, ± glabrescent in infructescence; prophyll not seen, presumably inserted at the base of the peduncle and included within the leaf sheaths; peduncular bract inserted at the apex of the peduncle, woody, with solid beak, the whole to 90 cm long, 3-5 mm thick, abaxially with conspicuous longitudinal grooves, at anthesis the peduncular bract splitting longitudinally and circumscissile at the insertion, leaving a collar-like scar, the bract curling up on drying after abscission, adaxially the bract smooth, shiny, yellowish green abaxially tomentose and longitudinally shallowly grooved; rachis very short, to 8-9 cm long, to ca. 4 x 2 cm diam., tapering to ca. 0.7 cm at the tip, bearing ca. 30-50 crowded, spirally arranged rachillae, each subtended by a short, triangular, acuminate, coriaceous bract 1.1-7.5 x 1.0-2.8 cm; rachillae glabrous and lacking white wax, yellowish, becoming crimson in ripe fruit, straight, rigid, held at a narrow acute angle to the rachis, 45-66 cm long, ca. 5-8 mm diam. at the base, tapering distally, each with a poorly defined swelling at the very base, proximally with a bare portion 15-18 cm long, distally bearing distichous triads in the proximal 13-19 cm, paired staminate flowers in the middle 11-17 cm and solitary staminate flowers in the distal 13-18 cm, rachilla bracts triangular 1-4 x 1-6 mm; floral bracteoles well developed, broad, rounded, striate, rather coriaceous, shorter than the rachilla bracts. Staminate flowers narrow ellipsoid, ca. 13 x 4 mm; sepals to 2 x 2 mm, joined in the basal 1 mm, distally triangular, free and imbricate, glabrous, not striate; petals coriaceous, ca. 12 x 3 mm, tapering to a short acute tip, basally very briefly joined, abaxial surface glabrous, lacking white wax, obscurely striate; stamens 15, filaments 2 mm, anthers elongate 8 x 1 mm, erect, ± basifixed; pistillode absent. Pollen not studied. Pistillate flowers in bud, irregularly globose to obscurely angled, 9 x 6 mm, perianths persistent and enlarging in fruit; sepals broadly imbricate, 8-9 x 5-6 mm; petals 8 x 7 mm, broadly imbricate with short valvate tips; staminodal ring membranous, ca. 1 mm high; gynoecium ellipsoid, 6 x 4 mm, stigmas pyramidal in bud, 2 mm high. Fruit 1-seeded, oblate, 16 x 24 mm, with a short triangular beak to 3 mm long, 4 mm wide at the base, dark purplish-black at maturity, smooth, becoming striate when dry, surface glabrous except the beak where minutely and obscurely scaly; mesocarp thin, fleshy 1 mm thick, with longitudinal fibres, endocarp 15 x 22 mm, very thin, scarcely lignified, pores rather obscure, just below the equator. Seed oblate 13 x 20 mm, attached near the base with a broad hilum, with numerous anastomosing raphe branches, endosperm deeply ruminate; embryo lateral below the equator. Germination: adjacent-ligular; eophyll entire, lanceolate.

Distribution:

Native to, Madagascar

Beccariophoenix alfredii experiences a subhumid temperate climate drier than that of the east of Madagascar. The average temperature is 15-20°C and frosts are frequent, the rainfall generally less than 1500 mm. The dry season is about five months long. The population of B. alfredii occurs at an average elevation of 1050 m above sea level; above that elevation, the palm becomes less common, although the satellite image shows palms growing at over 1700 m above sea level, meaning this is by far the more cold-tolerant Beccariophoenix (zone 9a). The soils in general in the region are ferralitic, but B. alfredii seems to grow solely on sandy soils on the banks of tributaries of the Mania River. Beccariophoenix alfredii is the dominant species in the gallery forest and, reaching mostly 10-15 m, constitutes the only canopy species. The species grows abundantly in the area. The dominance of this species may be due to the fallen leaves and inflorescences that carpet the ground, completely eliminating any other woody plants. Moreover, seed dispersal seems to be mostly by water. The flattened shape of the fruits allows them to be dispersed easily by water until they are deposited in a site favourable for germination. Sometimes seedlings are found actually growing in water but they mostly occur along the river bank.

Location: Madagascar. (-20.208628°N, 46.500977°E)

Observations
Map may not represent the complete natural distribution. (Markers display observation data).


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